pinctrl: add some comments to the hog/late init code

It confused me a bit so it may confuse others. Make it crystal
clear what is going on here for any future readers.

Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index d02e8def95061ea9d9b4b58448de3bc53b5470c1..a9e3a75fb67d5ed011caa7a306503ef974506c9b 100644 (file)
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -1753,6 +1753,12 @@ static void pinctrl_late_init(struct work_struct *work)
 
        pctldev = container_of(work, struct pinctrl_dev, late_init.work);
 
+       /*
+        * If the pin controller does NOT have hogs, this will report an
+        * error and we skip over this entire branch. This is why we can
+        * call this function directly when we do not have hogs on the
+        * device.
+        */
        pctldev->p = create_pinctrl(pctldev->dev, pctldev);
        if (!IS_ERR(pctldev->p)) {
                kref_get(&pctldev->p->users);
@@ -1847,6 +1853,12 @@ struct pinctrl_dev *pinctrl_register(struct pinctrl_desc *pctldesc,
                goto out_err;
        }
 
+       /*
+        * If the device has hogs we want the probe() function of the driver
+        * to complete before we go in and hog them and add the pin controller
+        * to the list of controllers. If it has no hogs, we can just complete
+        * the registration immediately.
+        */
        if (pinctrl_dt_has_hogs(pctldev))
                schedule_delayed_work(&pctldev->late_init, 0);
        else